Sum rules in zone axis STEM-orbital angular momentum resolved electron magnetic chiral dichroism

TL;DR

This paper derives sum rules for orbital angular momentum resolved EMCD, enabling evaluation of atomic magnetic moments, and demonstrates their robustness against dynamical diffraction effects through numerical simulations.

Contribution

It introduces new sum rules for OAM-resolved EMCD that are minimally affected by dynamical diffraction, simplifying experimental analysis.

Findings

Sum rules enable evaluation of spin and orbital magnetic moments.

Numerical simulations show minimal dependence on dynamical diffraction effects.

Application of sum rules is feasible without complex diffraction calculations.

Abstract

In this work we derive sum rules for orbital angular momentum(OAM) resolved electron magnetic chiral dichroism (EMCD) which enable the evaluation of the strength of spin and orbital components of the atomic magnetic moments in a crystalline sample. We also demonstrate through numerical simulations that these rules appear to be only slightly dependent from the dynamical diffraction of the electron beam in the sample, making possible their application without the need of additional dynamical diffraction calculations.